As I mentioned in an earlier post, when you fill something (ie. a glass) up to the top with water, the outside is still completely dry. However, when you immerse/baptise a glass, the outside is completely covered with water. The two are very different. It is the same when it comes to the filling and the baptism of the Spirit.
While I was looking into these two operations, I found a little chart that was extremely helpful to me to explain why these are different
Many people do confuse the baptism with the Spirit and the filling of the Spirit because on once occasion, the two operations did occur at the same time. On the day of Pentecost, we have recorded for us the initial descent of the Holy Spirit to earth - the coming of the Comforter. Many of the Jewish folks assembled there that day were already believers in the resurrected Lord Jesus Christ. However, these believers did not yet have the Holy Spirit living within them and were not yet part of the body of Christ, the church, simply because the Spirit had not yet come as Christ had promised. When the Spirit did come, accompanied by the sound of a mighty rushing win, these believers assembled in the upper room were finally "saved" in the New Testament sense of the word. The Holy Spirit baptised them into the body of Christ (1 Cor 12:13) and they in turn were baptised with the Spirit of God and were "born again" or regenerated.
However, another very important work of the Spirit occurred at this same time on this particular occasion. According to Acts 2:4, these same believers were "filled" with the Spirit of God for service. This filling was quickly evidenced in the bold and powerful preaching of the word of God that occurred throughout that day with many thousands of people coming to Jesus Christ as Saviour. The baptism with the Spirit that occurred in the hearts of these men was permanent - they were saved for eternity. Their filling, however, was not permanent and was later repeated.
There is no other passage of Scripture that records for us anyone being saved (baptised wit the Spirit) and filled with the Spirit on the same day. Paul comes very close in that he was filled with the Spirit of God three days after he was saved. We see this in Acts 9:17 when Saul/Paul is already a "brother" in the Lord when Ananias comes to see him three days after his conversion and then is filled with the Holy Spirit.
We must be very careful about building a doctrine on one portion of Scripture or upon the initial manner in which the Spirit of God dealt in a particular way - ie. the Day of Pentecost. The events of Pentecost were never repeated elsewhere in Scripture.
The main purpose of the filling of the Holy Spirit has nothing to do with speaking in tongues, or providing the believer with a prayer language. It's main purpose is to provide men and women with the power of God to deliver a message from God - Micah 3:8, Luke 4:14, Acts 1:8, 1 Corinthians 2:4, 1 Thessalonians 1:5.
Many people claim the main purpose of the baptism of the Spirit is about laughing in the Spirit, or being slain in the Spirit, etc. This is not the case as it's main purpose, when you look at Scripture and it's uses of "Baptism of the Spirit" is to put you into Christ and the body of Christ.
"For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ. For in one Spirit we were all baptized into one body--Jews or Greeks, slaves or free--and all were made to drink of one Spirit." - 1 Cor 12:12-13
In the above passage, the Greek construction (the verb "baptizo" and the dative of pneuma, "Spirit") is also used in the other six "baptism of the Holy Spirit" passages (Matthew 3:11, Mark 1:8, Luke 3:16, John 1:33, Acts 1:5 and Acts 11:16) Here it seems clearly to refer to the cleansing and empowering work that the Holy Spirit does in a new convert at the point of conversion. Baptism is used metaphorically here to refer to the Spirit's work within the believer to unite him or her to the body of Christ, which is also the corporate body of believers.
